Water Treatment Process Design for Rural Regions of Developing Nations This presentation highlights water treatment process design systems based on the field research performed in Rwanda. Jay Todd C. Max Senior Merit Research Scholar Viveka Pitter Senior Merit Research Scholar Faculty Supervisor: Professor Massoud Pirbazari Sonny Astani Department of Civil and Environmental Engineering Viterbi School of Engineering University of Southern California
47
Embed
Jay Todd C. Max · Giardia lamblia Diarrhea Filtration stages Somewhat Entamoeba histolytica Amoebiasis Multi-step filters Somewhat effective Cyclospora cayetanensis Watery Diarrhea
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Water Treatment Process Design for Rural Regions of Developing Nations
This presentation highlights water treatment process design systems based on the field research performed in Rwanda.
Jay Todd C. Max
Senior Merit Research Scholar
Viveka Pitter
Senior Merit Research Scholar
Faculty Supervisor: Professor Massoud Pirbazari
Sonny Astani Department of Civil and Environmental Engineering
Viterbi School of Engineering
University of Southern California
To the Visitor,
Your comments and suggestions would be appreciated. Please direct your thoughts to Jay Todd Max at [email protected]
Proposed Water Treatment Process Design for Rural Communities
Introduction:
• Bio-sand Filter Process
• For Visibly Clear water (<50NTU)
• Treats 60 liter/hr
• Provides for 10 families
• Full Treatment Process (Bio-sand filter plus pre-treatment)
• For Visibly High-Turbidity water
• Provides purified water for 90 families ( 5400
liters/day ) • Based on assumption of 3 Bio-sand Filters
operating 24hr/day, requires water storage following HRF
Concrete Walls or Wood Frame with Plastic Liner
Wood Roof-Support Columns
Corrugated Metal Roof or other Suitable Roof Materials
PVC or Metal Pipes with Spout Outlet
Cloth Filter placed on Perforated Metal Plate
Bio-sand Filter Process
Light Source
•Community Size: 50 people
Dimensions: 0.75m x 0.75m x 1.75m Max. Flow Rate: 50L/hr
•Community Size: 100 people
Dimensions: 1m x 1m x 2m Max. Flow Rate: 100L/hr
•Community Size: 200 people
Dimensions: 1.5m x 1.5m x 2m Max. Flow Rate: 225L/hr
Bio-sand Filter Design for Different Community Sizes
Components of Bio-sand Filter Process
• Biofilter Unit • The main component of Biofilter, where all of the treatment occurs and
treated water is stored
• Filter Cloth Frame • Perforated metal holds the cloth/fabric for initial filtration
• Roof • Protects from overheating and evaporation of filtering water • Allows for rainwater capture when possible
• Steps • Facilitate easy access to biofilter
• Light • Provides visibility for people needing water during sundown
• Out-spout • Easily dispenses desired amounts of water • Maintains desired water-level inside of tank to avoid tank from drying out
Cloth-Filter and Perforated Metal Plate Holder
•Cloth Filter (cotton/fabric) is placed on the perforated metal plate holder •The cloth filter provides initial filtration, removing •Water should be poured onto cloth filter rather than directly into biofilter •The cloth filter should be cleaned when necessary
Out-Spout Component
Water Level is about 1.70 m above the bottom of tank
Bottom of pipe is about 10 cm above the bottom of tank
Top of pipe is about 0.25m below the water level
Full Treatment Process
Note: water with low turbidity can be delivered directly to the Bio-sand filter, if desired
A
B
C
D
Schematics of Horizontal Roughing Filter (HRF)
Treatment Sequence: 1. Water is transported or pumped into water reservoir (A) 2. Water passes through HRF (B) and enters storage basin (C) 3. Water is pumped from storage basin (C) into bio-sand filter unit (D)
Legend A: Water Reservoir B: HRF Unit C: Storage Basin D: Bio-sand filter unit
Pump
Presentation Summary >1 billion people without safe water
Emerging waterborne diseases plague these vulnerable people
Most solutions are too expensive and/or too technical
Bio-sand Filter Process provides safe water when surface water is visibly clear, < 50NTU
Full Treatment Process ( HRF + Biosand Filter + Chlorination ) provides safe water direct from highly turbid source water
Field Research: Rwanda
By Jay Todd Max 2013
Bucket-bath Room
Briefing Translator Community Forum
Local Contacts
Motivation for Rwanda Field Research
• I was always interested in real-world observation of
water supply systems in developing countries
• I lived with my host-family in rural Rwanda in a mud-
brick house for 7 weeks, learning their way of life
• Rural communities in Rwanda have water supply
situations typical of the developing world
• I made quantitative and qualitative records of the water
system in the community, and of all input that the
community members gave
• The following slides show the information I garnered
and the analysis I was able to perform using that
information
My host-family in our house
Mama (in the blue/yellow conga) with
two daughters and three sons
Field Research: Rwanda
• Location: Bwana, Rwanda • Eastern Province
• Rwamagana District
• Rural Community (pop. ~200 people)
• Spoken Language: Kinyarwanda
• Economy: Agriculture
Case Study: Rwanda
• Water Sources
• Climate
• Rainy Seasons March-April-May and Sept.-Oct.-Nov.-Dec., otherwise DRY
• Environment
• Nearly 900-1200mm/yr rain
• Surface water area 430,000 ha of the total area of 2,630,000 ha (~14.6%)
• Transport/Distribution
• Surface water is pumped to communities and towns
• Pipe system carries water to local taps
• Jerry Can(s) transport water from taps to homes
Tap Jerry Cans
Case Study: Rwanda (continued)
• Typical water treatment
• Cities treat water using conventional methods
• Towns filter (but do not purify) surface water and pump it to some nearby communities
• Some rural communities have groundwater pumps
• Rural communities sterilize water by adding drops of chlorine solution to plastic containers full of water
• Cost Structure
• Currency: RWF-Rwandan Franc
• Conversion Rate
• About 600 RWF = 1 USD
• Costs 100,000 RWF (about $170 USD) to install a water tap with access to filtered water pumped from a nearby town
• Water costs 10 RWF per plastic container (20L) when pumped from a nearby town
Families filing their plastic containers with water from a hand-pumped groundwater well
Rwandan Franc coins (both sides) Community members purchase water pumped from nearby towns using these coins
Recommended Use of Bio-Sand Filter Process
Criteria of an appropriate location for Bio-sand Filter
Surface water is nearby
• Wetland, Lake or River
Community lacks distribution of filtered water
• It is rural, far from a city or town
• EWSA (Energy, Water and Sanitation Authority) piping does not reach this community
and/or
Can be particularly helpful in regions with frequent droughts
• East and Southeast Lowlands
Recommended Locations for Bio-Sand Filter use
Districts: Bugesera, Ngoma and Kirehe
• Mostly regions in the southeast
• These areas satisfy all of the above criteria
Bio-sand Filter will easily clean nearby surface water for safe use
The communities 6mi. south of the town of Munazi are good examples of where the Bio-sand Filter would be situated best
Location of Munazi
Implementation of Bio-sand Filter Unit
• Location
• Select a site according to recommendations on the previous slide
• Choose a central location within a village near surface water
• Construction
• Bio-sand Filter should be constructed according to the instructions given in the “Bio-sand Filter Design” slides
• Bio-sand Filter design incorporates the following components: concrete support slab, access steps and filter cloth holder
• The Bio-sand Filter should be covered with a sloped, corrugated-metal roof
• Dispensing
• The Bio-sand Filter requires one unit of water to be added to it for each unit of water dispensed; this keeps the filter from running dry
• Maintenance
• Cloth filter needs periodic cleaning
• Efforts should be made to establish a healthy biofilm layer on top of the bio-sand filter
Recommended Use of HRF Treatment Process
HRF treatment process may be appropriate for the following communities:
Community is near a river or other surface water (this requires a pump to convey water to the HRF)
Community lacks distribution of filtered water such as from EWSA
Community is in a region with frequent droughts (such as East and Southeast Lowlands)
Recommended locations for HRF treatment units
Along the southern stretch of the Nyabarongo River
In the southern lowlands of the Eastern Province
Implementation of HRF Water Treatment Process
• Location
• Site-selection according to prior slide
• Central location within village
• Near surface water
• Construction
• HRF should be constructed according to instructions presented in the previous slides
• If desired, pump HRF-treated water to a Bio-sand filter for further treatment
• HRF should be covered with a sloped, corrugated-metal roof
• Dispensing
• Maintain a supply of inflow water by pumping water into the first chamber of the HRF
• The amount of water that the pump supplies is how much water may be dispensed from the treated end